Process for charring or carbonizing peat.



No. 847,748. TENTED MAR. 19, 1907.

M. EKENBBRG.

PROCESS FOR GHARRING 0B. CARBDNIZING PEAT. APPLIGATION PILBDMAY 14.190s,

2 SHEETS-#SHEET 1,.

No.y 847,748.

PATBNTED- MAR. 19, 1907. M. EKENBERG.

PROGESSTORUHARRING 0R YGARBONIZING PRAT.

APPLIOATIUN FILED MAY 14, 1903.

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2 sums-SHEET z.

UNITED sTATEs PATENT oEFIoE.

MARTIN EKENBERG, or STOCKHOLM, swEDEN.

Specification of Letters Patent. v

PROCESS FOR CHAHRING OR CARBONIZING FEAT.

Patented March 19. 1907.

Application filedMay 14, 1903. VSerial No'. 157,177.

v To all whom, t may carecer-n,.-

Be it known that I, MARTIN EKENBERG, a

subject of the King of Sweden, residing at Stockholm, Sweden, haveinvented a new'A dried in the well-known manner or if it bepressed, aportion, but not all, of this water can be removed from the peat. Thereason why all the water cannot be removed from i thepeat by air-dryingor pressing seems to be that the peat contains minute chambers orso-callcd vesicles which are filled with water, and in compressin orair-drying the peat the water in the vesic es is not removed, althoughpractically all the water outside the vesicles is expelled. In thisspeciiication I shall refer to the water which is contained in thevesicles-that is, the water which cannot be removed from the peat orother substance by air-drying or pressing-,as vesicular water, and Ishall refer to the water which can be expelled by pressing or:tip-drying as mechanically-suspended Water.

Prior to my invention, so far as I am aware, it was considered necessain the treatment of peat rst to remove al or ractically all of themechanically-suspende water, either by air-drying, ressing, or by someequivalent operation, efore attempting to carbonize or char thepeat-that is,.to placeit in condition to be burned as fuel. Afterremoving the mechanically-suspended water the peat or other substancewasheated in a suitable apparatus, either by means of external heat orby heated gases or steam or electricity, in a manner analogous to orreseme bling dry distillation, by means of which heating the vesicularwater remaining in the peat, together with certain volatile products',were driven 0H as vapor or gas.' These prior processes were expensive onaccount of the time required by air-drying or the labor and power`required in pressing and by theexcessive heat necessary to 'maintainthe apparatus at; the proper temperature. during thecarbonizingoperation, especially when hot gases were used. Furthermore,the prior processes were objectionable by reason `of the fact thatexcessive heat frequently caused the accidental ignition ofthe peatwhile in the so-called charring or carbonizing apparatus.

present process is based on my dis? covery that if precautions be takento prevent vaporization of Water the peat or other substance can bethoroughly carbonized or rendered capable of use as fue-l without makingany effort to remove the mechanically-suspended water prior to theheating o eration and that after the heating operation as been concludedboth the mechanically-suspended water and the vesicular water can bereadily separated from the peat in any manner-such, for example, as byApermitting the peat to settle in the water. Furthermore, I havediscovered that the presence of the mechanically-suspendedA water so farfrom being detrimental during the heating operation, as formerlybelieved, is advantageous for two reasons: first, because it acts as anexcellent heat-conductor for transmitting heat uniformly rto allportions of the peat, and, second, because it prevents accidentalignition of the peat or other substance during the carbonizing orheating operation.

In this specification I do Anot desire to be limited to any technicaldefinition of the expression carbonization or carbonized peat. By theword carbonization @I mean the change which takes place in the peat asthe result of treatment according to my process and which enables thepeat to be burned as fuel, and by carbonized peat I mean peat which hasbeen rendered capable of ignition by treatment according to my process.v

My new process consists in taking peat practically as it comes from theboghthat is, peat containing practically the normal quantity ofmechanically-suspended water in addition to the vesicular water-and,without making any effort to remove the mechanically- .sus ended water,heating the mixture of peat an water in a suitable apparatus or `vesselin such manner that none of the water can eva 'crate .Y The lvessel lr apart thereof isv re erably heated to a temperature ranging om 15.0centigrade to 250 centigrade or higher, according to the kind of peat,for a period ranging from ten to forty minutes.

The temperature to be used and thedurawell-known IIO tion of the processdepend vupon the material to be treated and can be exactly ascertained'only by experience.

'4 For instance, mosses of the kmd called Sphagnum should be exposed forten minutes to a temperature of 150o centigrade.I Younger turf issuitably Va temperature of 250 centigrade.

exposed for twenty-five minutes to a temperature of 250 centigrade, andolder turf is preferably exposed for forty minutes to y Consequently` inoppositiont to hitherto-known methods a treatment of the peatexclusively in the presence 'of the mechanically-suspended water takesplace Without any Water being allowed to escape in the form of steam.The

,mechanically-suspended water present dur- .l of heat and' is to beavoided, since the heat used for'this purpose cannot be recovered.

According to my method no heat is wasted in evaporating water. f Y

The eiiiciency of the present new process seems to be largely due to thefact that the heat which vis uniformly transmitted by themechanically-suspended Water to all parts of the peat, as beforedescribed, causes the socalled vesicles to be changed, broken up,

ord estroyed, so that they are caused to liberate the vesicularwater-which they normally contain, this operation of causing thevesicles to liberate the vesicular water being aided by the extremepressure under which the process is carried out. The principaldifference between the present method and the old methods, therefore, isthat when the peat is pressed or otherwise treated accordingy to the pldmethods to expel preliminarily the mechanic-y ally-suspended Water thevesicles are not destroyed, and the considerable quantity of water whichthey contain is retained in the peat until it is subsequently heated inthe manner previously described with reference to prior processes todestroy the vesicles and expel the water as vapor, with the accompanyingrisk of igniting the peat. In my' process, on the contrary, instead ofexpelling .the mechanically-suspended water I utilize it as aheatconductor for uniformly heating the peat and releasing thevesicular, water, at the same time-preventing accidental ignition,whereby constant watchfulness of an attendant to prevent the temperatureof the heat from rising to the point of ignition is unnecessary.

My process may be carried out in any suitable apparatus; but in orderthat the practical working of ,the invention may be better understood anapparatus well adapted for the purpose is shown in the accompanyingdrawing, in which'- Figure 1 shows. the heating apparatus inlongitudinal vertical section,` and Fig. 2

shows in longitudinal vertical section a pulppump for feeding the Wetorv raw peat into the receiving-chamber 'of the heating appa-I ratus.

1 designates a plurality of horizontallydisposed metal tubesplacedwithin a brickwork structure 2, having at one end a iireaA place orfurnace 3. The tubes 1 are open toward the feeding-chamber 4, oftheapparatus, but closed at their opposite ends. Extending through thetubes 1 from the chamber 5, i

of inner tubes 6,' one wlthin each of the outer ones, said inner tubesextending to within a i short distance from the closed ends of. theouter tubes. The wet peat is placed 1n a hopper 7, Fig. 2, from which itis intermittently pumped or forced into the heating apparatus by meansof a plunger or lpiston S, driven in any suitable mamier. ger or pistonforces the vwet peat to pass a valve, suitably consisting of a hollowmetal ball 9. From the chamber 11 above the valve 9 the raw peat isbrought 'to a chamber 4, Fig. 1, at one end of the heating apparatus andcaused to enter the spaces between the outer and inner tubes 1 and 6. Atthe closed ends of the outer tubes 1 the material is caused to turn andmove through the inner tubes in a direction opposite to the direction ofmovement of the material in the spaces between the outer and innertubes. The material after having been heated in the furnace 3 is causedduring its passage through the portion of the inner tubes extendingthrough the right half of the heating apparatus to give oil' heat to thematerial moving toward the furnace and -linally reaches the chamber 5,from which it is led to the receptacle referred to above for separatingthe water from the treated product;

l/Vhat I claim is- 1. The herein-described process of treating asubstance which contains mechanicallysuspended water and vesicularwater, which process consists in subjecting the substance and water to atemperature sullicient to libcrate the vesicular water, withoutpermitting either the vesicular or mechanicallysuspendcd water toevaporate. during Jthe heating operation, whereby themechanically-suspended water acts as a heat-conductor during the heatingoperation for causing the liberation of the vesicular'watcr.

2. The herein-described process for treating eat, and other substanceswhich contain mec anically-suspended and vesicular wa- The plun- IOC:

IlO

peat and Water to a temperature of not less than 150 centigrade foraperiod. ranging from'ten to forty-minutes Without permitting any Waterto evaporate, andnally separating the peat from the Water, themechanically-suspended Water serving as a heat-conductor during theheating operation lto liberate the vesicular Water and to preventignition-of the peat. '1.

3. The herein-described process .of carbonization, which consists inheating the substance to be treated` in the presence oi a liquid', suchas,l water, without permitting any of the liquid to evaporate dring theheating x 5 operation, whereby the' liqi'd acts as a heatconductor fortransmittingheatto the suby stance to be treated.

In witness whereof Ihave hereunto si ed my name in the presence of twosnbscri ingzo ,Witnesses/ Witnesses;

ERNST SvANQvIsT,'. ROBERT APELGREN.

